PREEMPT_RT relies on PREEMPT_RCU - only allow RCU to be configured
interactively in the !PREEMPT_RT case.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

irttp_dup() copies a tsap_cb struct, but does not initialize the
spinlock in the new structure, which confuses lockdep.
Signed-off-by: Deepak Saxena <dsaxena@mvista.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Now that all users are cleaned up, we can remove the preemption count.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

With the separation of pagefault_{disable,enable}() from the
preempt_count a previously overlooked dependancy became painfully
clear.

kmap_atomic() is per cpu and relies not only on disabling the
pagefault handler, but really needs preemption disabled too.

Make this explicit now - so that we can change pagefault_disable().
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

With the separation of pagefault_{disable,enable}() from the
preempt_count a previously overlooked dependancy became painfully
clear.

kmap_atomic() is per cpu and relies not only on disabling the
pagefault handler, but really needs preemption disabled too.

Make this explicit now - so that we can change pagefault_disable().
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

With the separation of pagefault_{disable,enable}() from the
preempt_count a previously overlooked dependancy became painfully
clear.

kmap_atomic() is per cpu and relies not only on disabling the
pagefault handler, but really needs preemption disabled too.

Make this explicit now - so that we can change pagefault_disable().
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Add a pagefault_disabled variable to task_struct to allow decoupling
the pagefault-disabled logic from the preempt count.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

If trace_printk_on_oops is set we lose interesting trace information
when the tracer is enabled across oops handling and printing. We want
the trace which might give us information _WHY_ we oopsed.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

To allow macros pick the right implementation cast to (spinlock_t *).
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

PMU results are not useful if that ISR is run as thread.
Signed-off-by: Kevin Hilman <khilman@mvista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

 arch/arm/oprofile/op_model_xscale.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

No forced threaded handlers for these interrupts.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Add the IRQF_NODELAY flag and implicitely mark all timer interrupts
IRQF_NODELAY by redefining IRQF_TIMER.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

RT serializes the code with the (rt)spinlock but keeps preemption
enabled. Some parts of the code need to be atomic
nevertheless. 

Protect it with preempt_disable/enable_rt pairts.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

RT needs a few preempt_disable/enable points which are not necessary
otherwise. Implement variants to avoid #ifdeffery.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

The ktime_get() functions for GENERIC_TIME=n are still located in
hrtimer.c. Move them to time/timekeeping.c where they belong.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

The generic ktime_get function defined in kernel/hrtimer.c is suboptimial
for GENERIC_TIME=y:

 0)               |  ktime_get() {
 0)               |    ktime_get_ts() {
 0)               |      getnstimeofday() {
 0)               |        read_tod_clock() {
 0)   0.601 us    |        }
 0)   1.938 us    |      }
 0)               |      set_normalized_timespec() {
 0)   0.602 us    |      }
 0)   4.375 us    |    }
 0)   5.523 us    |  }

Overall there are two read_seqbegin/read_seqretry loops and a lot of
unnecessary struct timespec calculations. ktime_get returns a nano second
value which is the sum of xtime, wall_to_monotonic and the nano second
delta from the clock source.

ktime_get can be optimized for GENERIC_TIME=y. The new version only calls
clocksource_read:

 0)               |  ktime_get() {
 0)               |    read_tod_clock() {
 0)   0.610 us    |    }
 0)   1.977 us    |  }

It uses a single read_seqbegin/readseqretry loop and just adds everthing
to a nano second value.

ktime_get_ts is optimized in a similar fashion.

[ tglx: added WARN_ON(timekeeping_suspended) as in getnstimeofday() ]
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: john stultz <johnstul@us.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Timer interrupts are excluded from being disabled during suspend. The
clock events code manages the disabling of clock events on its own
because the timer interrupt needs to be functional before the resume
code reenables the device interrupts.

The mfgpt timer request its interrupt without setting the IRQF_TIMER
flag so suspend_device_irqs() disables it as well which results in a
fatal resume failure.

Adding IRQF_TIMER to the interupt flags when requesting the mrgpt
timer interrupt solves the problem.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

commit 58f53974 ([NET]: Can use __get_cpu_var() instead of per_cpu()
in loopback driver.) breaks on preempt-rt.

Use get_cpu() if -rt is enabled.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>